Hey @RufiAldayFresnoClovisCA! It sounds like you created a One-Off Meeting. 

One-off Meetings offer a quick and flexible way to host a one-time meeting that doesn't match your regular event type configurations. When you set up a One-off Meeting, you can use key event type settings like location, hosts, timing, and more.  

This type of meeting is useful when you need to:

• • quickly schedule a non-standard meeting with one or more hosts

  • offer your invitee times that fall outside of your regular availability

  • give a meeting higher priority over your existing meetings. 

Note: One-off meeting types create single-use links and are intended to allow a single invitee to book. Once an invitee books, the link will become invalid and you will see the error you noted in your post!

If you are hoping to allow many people to book via the same link for different time slots, consider a one-on-one event type or even using a Meeting Poll! Here's a great article that explains our Meeting Polls feature!

Once participants have voted in your poll, you can decide on the preferred time to schedule the meeting.

1. In your Calendly account, go to your Scheduled events page.
2. Select the Pending tab.
3. Find your preferred time to have the meeting, and select Book meeting time.
4. Confirm the invitee list looks correct, and then select Book meeting.

After you book
You and your invitees will receive a calendar invitation with the meeting details and location.

You might also benefit from Group Event Types! I hope this helps!